1. Field of the Invention
The invention relates to moldings and the installation of moldings.
2. Description of the Prior Art
Moldings are widely used to enhance the appearance of home interiors, and different kinds of moldings are available to suit different requirements. Thus, one kind of molding commonly employed serves mainly to hide gaps in corners and to protect corners from direct contact with people and objects. A more exclusive kind of molding has primarily an ornamental purpose.
Two general types of ornamental moldings exist. The first type of ornamental molding, which requires little skill to install, is made of wood or plastic. These moldings can be readily cut and are usually mounted on a wall and/or ceiling by means of nails or adhesive. Moldings of this type are disclosed, for instance, in Lit. Item #111500 of Georgia-Pacific Corporation entitled "Combination Moulding Designs" (May 1992) and brochure FT-210-5931 of Armstrong World Industries, Inc. entitled "Armstrong Finishing Touches--Mouldings and Medallions" (1993).
The second type of ornamental molding is made of plaster and requires a relatively high skill level for installation. Plaster moldings are produced in basically two ways. On the one hand, they can be run in place on a wall or ceiling or run on a bench. On the other hand, they can be cast in a stationary mold.
A run-in-place molding is made using a template which has the negative of the desired profile of the molding. Wet plaster is troweled onto the area which is to be provided with the molding and the template is thereupon run over the plaster. In order to guide the template, it is necessary to install wooden tracks adjacent the area being worked on. This is a difficult and time-consuming operation. Furthermore, if the molding is less than 1 inch thick, a bonding agent must be painted onto the area to be provided with the molding to increase adhesion. Even more work is required when the thickness of the molding exceeds 1 inch since the area being worked on then needs to be built out with blocks and covered with a wire lath.
The run-on-a-bench technique differs from the run-in-place technique in that the molding is produced on a special bench rather than in place. Depending upon its size, a run-on-a-bench molding can be directly mounted on a surface by means of a slip of gypsum plaster or can be installed in a backing box and nailed or screwed into studs, joists or a lath. Cast plaster moldings are likewise mounted differently depending on weight with plaster of paris, mastic adhesive, epoxy or gypsum board being used for lighter moldings and screws for heavier moldings.
When ornamental moldings are installed using nails or screws, the resulting holes must be filled and the filler smoothed by sanding. Since this entails a considerable amount or work, it is desirable to mount the moldings adhesively.
To reduce the number of materials required during the installation of moldings, the bonding agent for adhesive attachment of the moldings is preferably the same plaster-based material used to fill the joints between moldings. Inasmuch as plaster shrinks when it dries, a relatively great thickness of plaster-based material is necessary to achieve a good bond. To date, however, the art does not appear to have devised a bonding technique employing thick layers of plaster-based material.